The present invention relates to doors and a door manufacturing method and has particular applicability to traffic doors through which product-carrying carts and racks pass.
Impact resistant traffic doors of various constructions are known. For example, U.S. Pat. No. 5,528,865 to Johnson et al. discloses an insulated plastic molded door with integral hinge formed by rotational molding and filled with a foam filler. A bumper B is mounted to a lower portion of the door of this patent beneath a window W. The bumper B is formed by bending sheet material and fastening the sheet material to the door utilizing a plurality of fasteners. Doors of this type have been made with a similar bumper secured by fasteners to a portion of the door above the window W, although typically the upper bumper is narrower (shorter in height) than the lower bumper.
U.S. Pat. No. 5,459,972 to Eckel is understood to disclose a door having vacuum formed face panels mounted to door frame components including top, bottom, left side and right side peripheral frame members and interior cross-pieces. The face panels have contoured protuberances adapted to function as bumpers. In an illustrated form in FIG. 1, these bumpers are horizontally extending elongated protuberances having an elliptically curved contour in cross-section. In FIG. 1, these protuberances are three in number, are spaced apart, and are generally of an elongated oval shape. Matching protuberances project from the opposing front and back panels. In the illustrated Eckel door construction, a substantial number of component pieces are required to manufacture this door.
Although high impact traffic doors are known, a need nevertheless exists for an improved door of this type and also an improved method of manufacturing such a door. The invention is not limited to the specific embodiments described herein, but instead encompasses all novel and non-obvious aspects of the door and method set forth in the description below, both alone and in various subcombinations and combination with one another as set forth in the claims.